1) Technical Field
The present invention is directed to sewers and, more particularly, to an adjustable sewer inlet section for collecting and directing surface water drainage into a subterranean conduit.
2) Background Art
It is well known that most streets have openings which give access to vertical concrete cylinders leading to public services, namely aqueduct, energy and communications systems. While standards require the street draining well to be at a certain distance from the curb or the sidewalk, it is often difficult to locate the base of the street draining well so as to respect that distance.
Since all the components of a conventional street draining well system are stacked and do not allow for adjustments in position, it becomes impossible to obtain the required distance between the center of the grate and the sidewalk if the base is not positioned properly. In order to compensate for the bad positioning of the base, the upper components of the street draining well system will often be misaligned with respect to the base, This misalignment, in turn, will allow sewage water to infiltrate the street draining well system between the frame and the head, causing a premature erosion of the infrastructure supporting the roadway. The roadway surrounding the street draining well system then collapses, making the system both less efficient and dangerous. Furthermore, the infiltrated water freezes in the winter, causing an expansion of the ground surrounding the street draining well, and accelerating the degradation of its concrete components.
A depression in the roadway can frequently be seen around a street draining well. Asphalt roadways are almost watertight. Therefore, if the joint between the street draining well and the road is watertight; the infrastructure should stay dry. Due to the design flaws of conventional systems, in time, cracks start to appear in the road and water infiltrates the infrastructure under the road, which then collapses around the street draining well. The deterioration of the road is also caused by traffic and by the inadequate compaction of the infrastructure is surrounding the street draining well at the time of installation. In the case of existing street draining wells, the frame is fixed on a non compressible base that is set on stable ground and no damping elements are used between the base and the rigid frame with conventional street draining wells, we cannot compact the infrastructure without going around the sections of the street draining well. It is difficult, even impossible, to compact the infrastructure uniformly so that it stays stable with time. In time, the road collapses around the grate, which stays in place because it is fixed to a solid base.
Existing patents do not in any way resolve simply and efficiently the following frequently-encountered problems when installing street draining wells: unequal and deficient compaction of the infrastructure around the street draining well, incorrect inclination and alignment of the components of the street draining well with respect to the roadway, damages to the road and concrete components, non-conformity with public service requirements.
Canadian patent 1,068,961 discloses a sewer structure with threaded rods for adjusting the height and angle of a grate. Tools are required to adjust the position of the grate.
U.S. Pat. No. 5,470,172 and Canadian patent 2,151,069 discloses a sewer structure allowing for the adjustment of the height of a frame by adding a ring or multiple rings under the frame. A wedge may be inserted under the ring to set the inclination of the frame.
U.S. Pat. No. 4,906,128 and Canadian is patent 1,287,247 disclose structures which allow for the adjustment of the height of a grate. This is accomplished with a rod which is jagged and fixed in place by a protuberance.
U.S. Pat. No. 5,360,131 discloses a structure having two rings with inwardly projecting rectangular protuberances of different heights to allow the grate to attain the required height and slope by rotating the upper ring relative to the lower ring.
U.S. Pat. No. 5,051,022 discloses a structure that has a frame with a fixed sloped surface requiring different models to fit the different inclinations of the road.
Canadian patent 1,270,138 discloses a manhole with a movable cover that cannot be adjusted either in height or in inclination once installed.
In conclusion, some problems can only be partially solved by the aforementioned patents.